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1. Field of the Invention
The present invention relates to the transmission of real-time media signals over a data network and more particularly to a method and apparatus for controlling transmission of real-time media signals in a network-based teleconference.
2. Description of the Related Art
Long before the advent of personal computers and high speed data links, people have often found it necessary and efficient to meet with each other in person. In-person meetings facilitate face-to-face interaction and mutual exchanges. Further, such meetings are generally convenient to set up and execute, especially where the participants are located in the same geographic area. With the growth of the world market and the decentralization of businesses, however, in-person meetings are becoming less common. Workers are often geographically dispersed and therefore unable to meet with each other in person without traveling long distances.
A principle goal of modern teleconferencing systems is therefore to simulate in-person meetings. Teleconferencing systems do so by transmitting real-time audio and video signals over high speed data networks. Conference participants who would otherwise have been together in a physically common meeting place may then conveniently position themselves at multimedia teleconferencing stations that communicate over a network. Typically, each conferencing station includes a video camera and a microphone and a video display and sound speakers. Each participant may thus see and hear the others as though they were in a physically common location together.
Traditionally, network-based teleconferencing has been connection-oriented in nature. In a connection-oriented design, the conference participants must set up the conference call by having one conferencing station call another conferencing station. For instance, when a new person wishes to be added to a teleconference, typically the person must set up a station as a conference participant to communicate with the others over the data network. Unfortunately, however, by requiring active work by the participants when they wish to view and converse with each other, this system is unlike a meeting at a physically common location.
In order to make the teleconference more like a physically common meeting, a method of establishing seamless teleconferences is to leave the teleconference connection set up at all times between a pair of remote network locations. In this mode of operation, the transmitting end will continuously send audio and video over the network even when there is no one at the receiving end. Unfortunately, however, this solution is very inefficient and expensive, as it requires constant use of network resources and related infrastructure.
In view of the deficiencies in the existing art, a need therefore exists for an improved method of providing network-based teleconferencing.
The present invention provides a method and apparatus for controlling the transmission of real-time media signals over a data network based on a triggering event associated with a participating teleconference station. This triggering event may be the presence or absence of motion, the presence or absence of sound, or any of a variety of other events that preferably indicate the presence or absence of a person at the station. When no person is present at the station and/or when an appropriate triggering event occurs, remote teleconference participants will not transmit media signals over the network to the station, thereby conserving valuable network bandwidth. In turn, when a person is present at the station and/or when another appropriate triggering event occurs, remote teleconference participants may start transmitting media signals over the network to the station. Additionally, a station may control its own transmission of media signals to remote stations in response to local triggering events, thus further conserving network resources.
By controlling transmission over a network based on appropriate triggering events at participating teleconference stations, the present invention can beneficially simulate a physically common meeting between people, allowing a person to seamlessly join a teleconference by arriving at a participating station. Provided with the present invention, before a person arrives at the station, the station can be xe2x80x9cvirtually connectedxe2x80x9d to a teleconference, similar to an empty chair awaiting a person in a conference room. Once a person arrives at the participating station (as determined by a motion detector, for instance), the station may begin to receive and transmit media signals over the network, similar to a person entering a conference room, sitting in an empty chair, and beginning to interact with other participants.
It is therefore an object of the present invention to provide a method and apparatus for multimedia teleconferencing. It is further an object of the present invention to provide a method and apparatus for conserving network resources and processing power. Still further, it is an object of the present invention to provide a method and apparatus for simulating a physically common meeting between people.
Additionally, it is an object of the present invention to provide a method and apparatus for controlling transmission of media signals between teleconference participants in response to triggering events occurring at participating stations. Further, it is an object of the present invention to provide a method and apparatus for controlling transmission of media signals between teleconference participants in response to the presence or absence of a person at a participating station. Still further, it is an object of the present invention to control transmission of media signals over a network in response to the presence or absence of motion or sound at a participating station. Yet further, it is an object of the present invention to stop transmission to a participating teleconference station in response to an absence of motion at the station.
These and other objects and advantages of the present invention will become apparent to those of ordinary skill in the art by reading the following detailed description, with appropriate reference to the accompanying drawings.